1. Field of the Invention
The present invention relates to a suction device, and more particularly, to a suction device capable of attaching to a curved surface.
2. Description of the Prior Art
Suction devices are widely used for hanging items by attaching to a surface of an object in daily life. Please refer to FIG. 1 and FIG. 2. FIG. 1 is a three dimensional schematic diagram of a conventional suction device 10, and FIG. 2 is a side view diagram of the suction device 10 when attaching to a curved surface. As can be seen from FIG. 1 and FIG. 2, since a base of a support unit 100 of the suction device 10 is circular, when the suction device 10 attaches to the curved surface, there is a wide gap between a rim of the base of the support unit 100 and the attached curved surface. Therefore, a suction cup 102 of the suction device 10 fails to attach to the curved surface closely as expected, causing air leak. As a result, the general suction device 10 can only attach to a plane surface, and is not suitable for attaching to a curved surface.
Take a car holder for example. One end of the conventional car holder is a suction device, which has the same structure as the suction device 10 in FIG. 1, utilized for attaching to a windshield in front of a car, and the other end of the conventional car holder is a holding seat for placing car electronics, such as a satellite radio or a satellite navigation device. However, since the suction device 10 is not suitable for attaching to a curved surface, the conventional car holder can only be fixed on a plane surface of the windshield in front of the car, and can not be fixed on a curved surface of other internal parts of the car, such as a dashboard. However, the line of sight of a driver may be blocked due to the car holder fixed on the windshield, causing a driving issue. Besides, the windshield is far from the front seats, and thus the user can not install the car holder easily. From the above, if a suction device can not attach to a curved surface closely, the application of the suction device is limited.